Method of constructing a composite form

ABSTRACT

A composite slab casting form particularly adapted to resist the transverse deflection forces generated by the weight of concrete in the form. The base or pan of the form is constructed from a relatively thick, flat, plate member having a pair of longitudinally extending notches machined in its upper surface. A pair of relatively thin liner plates are bent about longitudinally extending axes to form base leg portions and side leg portions joined by a smoothly curved connecting section. The liner plates are mounted on the pan with the base leg portions thereof received in the notches. Longitudinally extending voids are defined by the inner ends of the base leg portions and opposing portions of the notches in the pan and these voids are filled with a welding material, which is thereafter ground to provide a smooth flat surface coplanar with the upper surface of the pan and the adjoining surface of the liner plate. In bending the liner plates to provide the base and side leg portions the base leg portions are formed long enough to space the above mentioned welding material far enough away from the connecting section that the welding material can be readily ground with conventional tools without gouging, undercutting or otherwise blemishing the surfaces of the form.

United States Patent [19] Shoe et al.

METHOD OF CONSTRUCTING A OMPQSW IEWFQR Inventors: Theodore W. Shoe, Fletcher; Robert E. Smith, Kettering, both of Ohio Assignee: The Flexicore Co., Inc., Dayton,

Ohio

Filed: Apr. 2, 1973 Appl. No.: 347,151

Related US. Application Data Division of Ser. No. 207,189, Dec. 13, 1971, Pat. No. 3,750,998.

us. c1. 29/4713, 29/483 1m. 01...; ..B23k31 /02 Field of Search 29/471.1, 471.3, 475, 481,

[56] References Cited UNITED STATES PATENTS 6/1956 StrayL..." 29/483 X 7/1956 Breber et al. 29/483 X Primary ExaminerRichard-B. Lazarus Attorney, Agent, or Firm'-Biebel, French & Bug

451 July 16,1974

A composite slab casting form particularly adapted to resist the transverse deflection forces generated by the weight of concrete in the form. The base or pan of the form is constructed from a relatively thick, flat, plate member having a pair of longitudinally extending notches-machined in its upper surface. A pair of relatively thin liner plates are bent about longitudinally extending axes to form base leg portions and side leg portions joined by a smoothly curved connecting section. The liner plates are mounted on the pan with the base leg portions thereof received in the notches. Longitudinally extending voids are defined by the inner ends of the base leg portions and opposing portions of the notches in the pan and these voids are filled with a welding material, which is thereafter ground to provide a smooth flat surface coplanar with the upper surface of the pan and the adjoining surface of the liner plate. In bending the liner plates to provide the base and side leg portions the base leg portions are formed long enough to space the above mentioned welding material far enough away from the connecting section that the welding material-can be readily ground with conventional tools without gouging, undercutting or otherwise blemishing the surfaces of the form.

ABSTRACT METHOD CONSTRUCTING A COMPOSITE LJORM CROSS REFERENCE TO RELATED APPLICATION This is a division of application Ser. No. 207,189 filed Dec. 13, 1971 now U.S. Pat. No. 3,750,998.

SLAB CASTING FORM filed on even date herewith now U.S. Pat. No. 3,790,120.

BACKGROUND OF THE INVENTION from. In casting wider slabs, however, difficulties are.

encountered due to the increased transverse deflection forc'eslgenerated by these wider slabs. Since the lower surfaces of the slabs serve as finished ceilingsurfajces theyrnust be relatively flat.

The invention disclosed in the above noted,.related"i application overcomes these difficultiesby forming the.

pan of the casting form as a plate of thick steel having a pair of notches machined in its uppersurface. A pair of relatively. thick side plates are provided which are machined to provide each of them with an upstanding side leg portion joined by a radius to an inwardly projecting base leg and an inwardly projecting groutkey cavity forming protrusion projecting inwardly from the side leg. The side plates are mounted in the notches with the bottom edges of the side plates engaging the bottom wall of each of the notches. The cavities formed by theinner ends of the base legs and opposing walls of the notches are filled with welding material which is then ground to provide a smooth flat surface.

The form thus constructed provides a solution to the problem of increased transverse deflection forces encountered in casting relatively wide concrete slabs and by machining the side plates so that the baselegs extend inwardly from the curved connecting portions a sufficient distance, the welding deposited in the cavities described above may be ground without damaging adjacent surfaces of the form. This is important of course,

since, as noted above, the' lower surfaces of the slabs serve as finished ceiling surfaces. Additionally, undercutting in the vertical walls of the form may lead to difficulties in form stripping and chipping. It will be apparent, however, that the construction of a form as described above will involve expenses of machining the side plates to provide the desired configuration and that it would be desirable to avoid this expense while still retaining the advantages of the invention.

. SUMMARY 0F THE INVENTION present invention includes a relatively thick, flat, base plate or pan adapted to resist the transverse deflection forces encountered when the form is filled with concrete. Additionally, the pan is provided with a pair of longitudinally extending recesses adapted to receive portions of the side wall members and the inner ends of these members are spaced inwardly of the form so an ivit ti pres ntintsm it I tib'nalwi'ew hrough the" form of 'SFIG. 1. t 1

' 1iDEscRiP noNoFTHeiinEFERRED 2 that there is little danger o f marring the surface of the form during grinding operations.

However, rather than forming the side walls of the form from relatively thick side plates machined to the desired contour, a pair of relatively thin side plates are utilized, bent about longitudinally extending axes to provideside leg portions and base leg portions interconnected by a smoothly curved section. As in the.

above noted related application, "the inner ends of the base leg portions extend far enough into the form away from the intersection of the base and side legs such that welding material deposited along the inner ends of the base legs may be ground down flushwith adjoining surfaces without gouging the form.

A pair of flat reenforcing plates may be also utilized having their lower edges received in the notches in the pans and their inner surfaces in underlying relationship to outer surfaces of the side' plates in the region of the side legportions the'reof; t

"BRIEF DESCRIPTION din-T ns DRAWINGS FIG. 1 is'an' isornetrievr sj'ho 'ng a form in accor:

- EMBODIMENT As seen'in FIGS. 1 and 2 of the drawings, a form 10 in accordance withthe present invention includes a relatively thick base plate 12 somewhatwider than the desiredwidth of the slab to be cast therein. For example, the base plate 12 might be approximately inches wide if slabs of approximately 4 feet in width are to be produced. Spaced inwardly of its longitudinally extending side edges 14 the base plate 12 is provided with longitudinally extending notches 16.

A pair of reenforcing plates 18, which may also be of substantialthickness, have their lower edges20 received in the notches 16 with a lower portion of their outer, faces 22 abutting an outer wall 24 of the notch 16 and their lower surface 20 engaging the opposed surface of the notch-16. The reenforcing plates 18 are then secured to the base plate 12 by means of welding, as indicated at 26 and 28.

Positioned within the form 10 are opposed pairs of upper and lower side plate sections 28 and 30, respectively. Each upper side plate section 28 includes an upper portion 34, which extends substantially perpendicularly with respect to an upper surface 36' of the base member 12, and a lower portion 38 which slants inwardly away from the base of the form and from A composite slab casting form in accordance with the which protrusions 39 are stamped or otherwise formed. Protrusions 39 in a finished slab will form a series of interrupted cavities to permit adjacent slabs to be keyed to each other with grout. The proper spacing of the upper portion 34 of the side plate 28 is maintained by means of spacer plates 40 positioned between the upper sections 34 and the reenforcing plates 18 and secured thereto by welding.

The lower sections 30 each include a side leg 42 overlying a bottom-portion of the reenforcing plate 18 and a base leg 44 connected thereto by means of a smoothly curved section 46. The spacedbetween the lower edge of each of the upper side plate sections 28 and the upper edge .of the lower side plate sections 30 is filled by means of welding, as indicated at 48 and this 3 weld is ground or finished to provide a smooth surface. Additionally, it will be noted from FIG. 1 that the ends of the form will be sealed, as at 50 and 51, to prevent the penetration of foreign material between the various elements of the form.

The voids defined by the inner ends 52 'of the base legs 44 and the adjacent walls of the notches 16 are filled by means of a weld material 53, which is thereafter ground to provide a smooth continuous transition between the upper surfaces of the base legs and the base plate. A cap member 54 is secured to the upper edge of the upper side plate section 28 and the upper edge of the reenforcing plate 18 by means of welds or the like, and projects outwardly over the longitudinally extending legs 14 of the base plate 12.

Because the base legs 44 extend inwardly of the form and thereby position the welds 53 a distance inwardly of the'curved sections 46, the welds 53 may be ground by means of conventional tools without danger of gouging adjacent portions of the form, as would be the case if the liner plates terminated at or near the curved portions 46 thereof. As a result, gouging of the form surfaces, which would retract from the usefulness of the slabs in providing finished ceilings, and the formation of undercut areas in the vertical walls of the form, which would hinder the removal of the slabs from the forms, is obviated.

Additionally, because the side plates are of relatively light gauge material, as compared to the thickness of the base plate 12 for example, they may be shaped by stamping to provide a shape difficult to produce by machining, such as the smoothly curved sections 46 and the protrusions 32. Also as a result of the use of thin side plates, the depth of the notch 16 in the base plate may be maintained at a minimum. Since, as noted above, the base plate will be flexed by a, stripping fixture to remove the cured slab therefrom, it is desirable,

from a standpoint of structural integrity of the base plate, to remove as little material as possible in forming the notch 16.

While the side plates are described as formed in separate upper and lower sections, it will be apparent that the upper and lower sections may be combined and each side plate formed from a continuous sheet of metal. Additionally, although the upper sections of the side plates .are formed with a series of protrusions to provide interrupted grout keying cavities in the finished slab, it will be apparent that a continuous, inwardly projecting rib could also be used to provide longitudinally extending grout keying cavities on each side of the finished slab. However, where keying against horizontal as well as vertical inter slab movement is desired,

the construction described above will be preferred.

The thickness of the pan should be between approximately three-eighths inch and three-fourths inch with the optimum thickness being approximately five-r eighths inch. Thus, the pan must be thick enough to resist deflection, since the finished slab must be relatively flat for purposes of appearance as well as for structural reasons, and the maximum thickness of the pan is controlled by a consideration of. the tensile strength of the formed therein of approximately three-sixteenths inch in depth and the side plates approximately the same thickness as the depth of the notches l6 and having a radius of bend of from five-eighths inch to one-fourth inch, with three-eighths inch an optimum. The face 24 of the notch 16 may be spaced inwardly from the edge 14 of the base plate a distance of approximately 2 inches and the reenforcing plate 18 have been formed approximately 1% inch in thickness.

The cap member 54 may be 1 inch in thickness and approximately 4% inches in width and overhang longitudinally extending edges 14 of the base plate about an inch, while the spacer plate 40 may be approximately 1% inch in height and five thirty-seconds inch in thick ness. Conveniently, the interior width of the form may be approximately 4 feet or more, although it may be of course be narrower for filler or other narrow slabs, and the overall height and length of the form of convenient dimensions for commercial operation. For example,

the internal depth of the form may range from 6 inches to 16 inches while the length of the form may be approximately feet.

While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. A method of constructing a form comprising:

a. providing an elongated, substantially planar, relatively thick base plate,

b. forming a pair of spaced, parallel recesses in an upper surface of said base plate,

c. providing a pair of elongated side plates of substantially less thickness than said base plate,

d. bending said side plates about an axis extending longitudinally thereof to form a substantially planar base leg, a side leg extending substantially perpendicularly to said base leg and a smoothly curved radius section interconnecting said base and side legs,

e. attaching said side plates to said base plate with said base legs received in said recesses and an inner end of said base leg spaced from a wall of said recess and defining therewith a void,

f. filling said void with a hardenable material, and

g. grinding said material to provide a smooth, flat transition surface betweensaid upper surface of said base plate and a corresponding upper surface of said base leg.

2. The method of claim 1 wherein:

a. said step forming said recesses in said upper surface of said base plate comprising forming said recesses at least as deep as the thickness of said side plates.

3. The method of claim 2 wherein:

a. said step of forming said recesses in said upper surface of said base plate comprises forming said recesses of a depth substantially equal to the thickness of said side plates.

4. The method of claim 1 further comprising:

a. providing a pair of reenforcing plates, and

b. mounting said reenforcing plates on said base plate in underlying relationship to said side legs.

5. Th method of claim 4 wherein:

a. said step of providing said reenforcing plates comprises providing a pair of reenforcing plates of substantially greater thickness than said side legs.

6. The method of claim 4 wherein:

a. said step of mounting said reenforcing plates on said base plate comprises mounting said reenforcing plates with longitudinally extending edges thereof received in said recesses.

7. A method of constructing a form comprising:

a. providing an elongated, substantially planar base plate,

b. providing a pair of elongated, relatively thin side plates,

c. forming longitudinally extending recesses having a depth substantially equal to the thickness of said side plates in an upper surface of said base plate,

d. bending said side plates about axes extending longitudinally thereof to provide base and side legs disposed substantially perpendicular with respect to each other and joined by a smoothly curved radius section,

e. providing a pair of elongated reenforcing plates having thickness greater than. the thickness of said side plates,

f. mounting said reenforcing plates on said base plate .with longitudinal edges of said reenforcing plates received in said recesses,

g. mounting said side plates on said base plate with said side legs overlying said reenforcing plates and said base legs received in said recesses with inner ends of said base legs spaced from opposed walls of said recesses to define therewith longitudinally extending voids,

h. filling said voids with welding material, and

i. grinding said welding material down to a coplanar relationship with an upper surface of said base legs and said upper surface of said base plate to provide a smooth transition surface therebetween. l 

1. A method of constructing a form comprising: a. providing an elongated, substantially planar, relatively thick base plate, b. forming a pair of spaced, parallel recesses in an upper surface of said base plate, c. providing a pair of elongated side plates of substantially less thickness than said base plate, d. bending said side plates about an axis extending longitudinally thereof to form a substantially planar base leg, a side leg extending substantially perpendicularly to said base leg and a smoothly curved radius section interconnecting said base and side legs, e. attaching said side plates to said base plate with said base legs received in said recesses and an inner end of said base leg spaced from a wall of said recess and defining therewith a void, f. filling said void with a hardenable material, and g. grinding said material to provide a smooth, flat transition surface between said upper surface of said base plate and a corresponding upper surface of said base leg.
 2. The method of claim 1 wherein: a. said step forming said recesses in said upper surface of said base plate comprising forming said recesses at least as deep as the thickness of said side plates.
 3. The method of claim 2 wherein: a. said step of forming said recesses in said upper surface of said base plate comprises forming said recesses of a depth substantially equal to the thickness of said side plates.
 4. The method of claim 1 further comprising: a. providing a pair of reenforcing plates, and b. mounting said reenforcing plates on said base plate in underlying relationship to said side legs.
 5. Th method of claim 4 wherein: a. said step of providing said reenforcing plates comprises providing a pair of reenforcing plates of substantially greater thickness than said side legs.
 6. The method of claim 4 wherein: a. said step of mounting said reenforcing plates on said base plate comprises mounting said reenforcing plates with longitudinally extending edges thereof received in said recesses.
 7. A method of constructing a form comprising: a. providing an elongated, substantially planar base plate, b. providing a pair of elongated, relatively thin side plates, c. forming longitudinally extending recesses having a depth substantially equal to the thickness of said side plates in an upper surface of said base plate, d. bending said side plates about axes extending longitudinally thereof to provide base and side legs disposed substantially perpendicular with respect to each other and joined by a smoothly curved radius section, e. providing a pair of elongated reenforcing plates having thickness greater than the thickness of said side plates, f. mounting said reenforcing platEs on said base plate with longitudinal edges of said reenforcing plates received in said recesses, g. mounting said side plates on said base plate with said side legs overlying said reenforcing plates and said base legs received in said recesses with inner ends of said base legs spaced from opposed walls of said recesses to define therewith longitudinally extending voids, h. filling said voids with welding material, and i. grinding said welding material down to a coplanar relationship with an upper surface of said base legs and said upper surface of said base plate to provide a smooth transition surface therebetween. 